Objectively speaking, 4K net / month is (well) above average (which is some 1900 I think). So you should be good.
But then again, life style is subjective, so it depends on what is a nice neighborhood to you, type of car, health and car insurance, holidays, eating out, etc.
I find this the best tool for making personal/subjective calculations:
https://www.numbeo.com/cost-of-living/compare_cities.jsp?country1=Argentina&country2=Spain&city1=Buenos+Aires&city2=Barcelona
It says "You would need around 3,142.91€ in Barcelona to maintain the same standard of life that you can have with 2,245.66€ (46,000.00ARS) in Buenos Aires (assuming you rent in both cities)".
So think about how much you spend now (more or less than 2245) and apply the same ratio to 3142 to see how much you'd need.
Wish you all the best with your new life in Barcelona, it's an amazing place!